Effect of different doses and application methods of sodium selenate on selenium status in maize for silage

A two-year field study was conducted to determine the effect of different Se fertiliser application methods and application rates on the selenium content in maize plants. Selenium as sodium selenate was added into soil (10 g and 20 g Se ha-1) or sprayed on maize plants (20 g Se ha-1). Maize plants from control treatment contained 0.018 and 0.020 mg Se kg DM-1 in the first and the second year of the study. Foliar application exhibited superior effect by increasing selenium content in the plants up to 0.343 mg kg DM-1 in the first year, and 0.249 mg kg DM-1 in the second. Soil selenium application was less effective; selenium content in maize plants varied from 0.018 to 0.019 mg kg DM-1 in the first and from 0.018 to 0.145 mg kg DM-1 in the second year, respectively. Strong linear correlation (r=0.71) was found between selenium content in the plants and in grains. Selenium recovery rates were significantly higher in case of foliar treatment compared to soil application.